Use a Raspberry Pi to hack la Fonera 2100

Now that I have a great pfSense box with Wi-Fi, I don’t need my Fonera 2100 anymore. So, why not try to do something interesting with it? 😉

At you can read how to access the serial console on the Fonera.

The serial port of the fonera uses 3.3V instead of the normal RS-232 voltage levels. Because of that, you need some level converters to connect the Fonera to a normal serial port.

But, the Raspberry Pi also has a serial port which operates at 3.3V. This means that you can connect the serial port of a Raspberry Pi and la Fonera without the need of a level shifter.



With a serial communication program like minicom it is now possible to access the Fonera.

starting minicom -b 9600 -D /dev/ttyAMA0

minicom : fonera booting

7 comments for “Use a Raspberry Pi to hack la Fonera 2100

  1. Aldo
    December 8, 2012 at 12:20 am

    I have tried to follow your article and connected my raspberry and the fonera as you suggest.
    But when i run nimicom with the same command line you gave, it stops at CTRL-A line and nothing happens.. any suggestion?
    I have doublechecked the cable and it works…

    Thank you,

    • December 8, 2012 at 5:15 pm

      What has worked for me, is:

      Connect the serial cable to the Raspberry Pi, but not to the Fonera. Boot up
      the Raspberry Pi and start minicom. Power the Fonera and after that, plug in the
      serial cable in to the Fonera.

  2. Aldo
    December 9, 2012 at 3:23 pm

    Hi Jan,
    thank you for your reply.
    I have double checked the cable and it is ok. I have tried to follow steps described it is still not working.
    My Fonera has 0.7.1 r2 original firmware on board, while I’m running raspbmc on my raspberry pi.
    It seems like nimcom freezes after the ctrl+a line, and after a while I have to disconnect from ssh session and reconnect again..
    Do you have any other suggestions please?
    Thank you!

    • December 9, 2012 at 5:08 pm

      Minicom starts up, so it doesn’t seems to be a problem with permissions.
      Mmm, I don’t directly have an idea what could be wrong.

      What do you mean with minicom freezes after the ctrl+a line? Can you bring up minicom’s menu with CTRL-A Z?

      • Aldo
        December 16, 2012 at 2:12 am

        Don’t know what to say.. I have tried with another fonera of a friend with dd-wrt and it works.. with the original one it just seems to freeze.. therefore I connected it using a serial connector, and a usb to serial converter and it worked.
        Thank you for your support, have a nice day!

      • Elkin Fricke
        November 29, 2013 at 8:55 pm

        using raspbmc?

        sudo nano /etc/init/ttyAMA0.conf

        and comment out the part with AMA0

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